How to push new items to an array inside of an object

Question

My JSON currently looks like this:

{
    \"_id\" : 393,
    \"item\" : 34,
    \"comments\" : [
        {
            \"name\" : \"kevin\",
            \"message         


        

Answer 1

Using $elemMatch and $ operator you can update your documents check below query :

db.collectionName.update({"_id":393,"comments":{"$elemMatch":{"name":"kevin"}}},
                         {"$push":{"comments.$.messages":39}})

Answer 2

Something like this will work:

var newMessage = '39';
comments.forEach(function(item) {
   if (item.name === 'kevin') {
        item.comments.push(newMessage);
   }
});